Electrical translating apparatus



Feb. 17,, 1931. DOWLING 1,793,213

ELECTRICAL TRANSLATING APPARATUS Filed Nov. 20, 1929 .Bv Y

ix6 l/"| f E z 13 NVENTOR Patented ch, 17, 1931 UNITED STATES PATENT OFFICE PHILIP H. BOWLING, OF SWISSVALE, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH & SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION 01 PENNSYLVANIA ELECTRICAL TRAN SLATING APPARATUS Application filed November 20, 1929. Serial No. 408,657.

My invention relates to electrical translating apparatus, and particularly to apparatus of the type comprising an input circuit which is at times supplied with current and an output circuit in which the flow of current is controlled in accordance with the current supplied to the input circuit.

I will describe one form of electrical translating apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawing, Fig, 1 1s a View, partially diagrammatic, show1ng 1n elevation one form of electrical translating apparatus embodying my invention. Fig. 2 is an end View of the apparatus shown in Fig. 1 to which have been added diagra mmatic representations of the control circuits.

Similar reference characters refer to similar parts in both views.

Referring to the drawing, the reference character A designates a transformer having a source of magnetomotive force here shown as an electromagnet C comprising'a magnetizable core 1 terminatin inspaced pole .pieces 2 and 3 and carrying a primary winding 4: which is supplied with alternating current from some convenient source, such as an alternator G. The reference character B designates a magnetizable core designed to provide a magnetic circuit analogous to the well known VVheatstone bridge. Thus it will be seen that the core B has four legs 5, 6, 7 and 8 connected in the form of a square, the opposite corners of which (points W and X) are connected by a bridging member 9. The pole pieces 2 and 3 of magnet C are adjacent the remaining corners (points Y and Z) of the magnetic bridge, and it follows, therefore, that the magnetic flux from magnet C flows through two paths in parallel, one path through legs 5 and 6 and the other path through legs 7 and 8. The bridging member 9 is provided with a secondary winding 10 and the parts are so proportioned that under normal conditions, the bridge is balanced, so that there is substantially no flux from magnet C linking winding 10. Under these conditions, of course, there is no electromotive force induced in winding 10.

The secondary winding 10 may be used to supply current to an electro-resp'onsive device of any suitable type and as here shown this winding is connected with an output circuit including an electric lamp 21.

In order to control the flux through winding 10 in accordance with current in an input circuit, the core B is provided with three arms 11, 12 and 13 projecting outwardly from the leg 7 and connected at their outer ends by a back strap 22. A winding 17 is located on arm 11, and it will therefore be seen that current supplied to the winding will produce flux which traverses two paths, one through arm 11, leg 7, arm 12, and back strap 22, and the other through arm 11, leg 7, arm 13 and back strap 22. In similar manner, there are outstanding from leg 6, three arms H, 15 and 16 connected at their outer ends by a back strap 23. l/Vinding 18 located on arm 1- is arranged when supplied with current to create a flux Which divides into two paths, one including arm 1%, leg 6, arm 16 and back strap 23, and the other including arm let, leg 6, arm 15 and back strap 28. The two windings 1'? and 18 are connected with an input circuit which is at times supplied with current from any suitable source. This input current may be alternating current of a frequency different from that delivered by alternator G or may be direct current, and as here shown, direct current is supplied from a battery 19 over a contact 20 to Windings 17 and 18 in series.

In explaining the operation of the apparatus, I will first assume that contact 20 is open, as shown in the drawing. The parts are so designed, as previously described, that no flux links winding 10 under these conditions, because the magnetic bridge is balanced, and points W and X are at substantially the same magnetic potential. Lamp 21 is therefore extinguished. 1f now, the

contact 20 is closed, current supplied to windings 17 and 18 create in these windings, fluxes which traverse the paths previously described. It should be pointed out in this connection that'the fluxes created in windings 17 and 18 do not link the winding 10, but the flux created in winding 17 increases the reluctance of leg? to flux from magnet C, and in similar manner, the flux created by current in winding 18 increases the reluctance of leg (3 to flux from the magnet C. Sincethe reluctanres of legs 5 and 8 are substantially unafi'ected, it follows that the magnetic bridge becomes unbalanced and a resulting flux flows from magnet C through winding 10. If the flux density in legs 6 and 7 is suflici-ently great to saturate these legs, a predominating portion of the flux from magnet C traverses the path from pole piece 2, through leg 5, bridging member 9 and leg 8 to pole piece 3. As a result of the flux now threading winding 10, there is induced in this winding an electromotive force which creates a current in the output circuit and lights lamp 21. It should be pointed out, however, that under no conditions, can flux from magnet C thread the input windings l7 and 18 so that it is impossible to produce feed back from the apparatus to the input circuit.

It should also be pointed out that the parts may be arranged in such manner that a comparatively small change ininput current will cause a comparatively large change in the output current. Furthermore, in apparatus embodying my invention, the change in the output current due to a change in the input current is practically independent of the total output current. In other words, the apparatus permits a comparatively large percentage change in output current.

Another advantage of apparatus embodying my invention is that since the flux paths for the input windings and the primary winding are entirely separate, the apparatus is safe from improper operation duerto short circuits or open circuits in any of the control windings.

Although I have herein shown and described only one form of electrical translating apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims Without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a magnetizable core comprising four legs connected in the form of a square, primary means for applying an alternating magnetomotive force to said core across two opposite corners of said square, a bridging member connecting the other two corners of the square in such manner that the resultant flux through said member due to said primary means is normally zero, a winding on said bridging member, and means for at times independently creating in at least one leg of said core a flux which does not thread said winding but which causes a resultant flux from said primary means through said winding.

,2. In combination, a magnetizable core comprising four legs connected in the form of a square, primary means for applying an alternating magnetomotive force to said core across two opposite corners of said square, a bridging member connecting the other two corners of the square in such manner that the resultant flux through said member due to said primary means is normally zero, a first winding on said bridging member, a second winding associated with said core in such manner that flux created by current in said second winding traverses one said leg of the core but not said bridging member, and means for at times supplying current to said second winding to cause a resultant flux from said primary means through said first winding.

3. In combination, a magnetizable core comprising four legs connected in the form of a square, primary means for applying an' alternating magnetomotive force to said core across two opposite corners of said square, a bridging member connecting the other two corners of the square in such manner that the resultant flux through said member due to said primary means is normally zero, a winding on said bridging member, and means for at times independently creating in two opposite legs of said core fluxes which do not thread said winding but which cause a resultant flux from said primary means to thread said winding.

4. In combination, a magnetizable core comprising four legs and a bridging member connected to form a magnetic bridge, a first winding on said bridging member, means for applying an alternating magnetomotive force across opposite corners of said bridge in such manner that the resulting flux through said first winding is normally zero, a magnetic path including one leg of said core, a second winding on said path, and means for at times supplying current to said second winding to cause a resultant flux from said first mentioned means through said windin 5. In combination, a source of magnetomotive force, two magnetic paths connected in parallel across said source, a bridging member connecting a point on one said path with a point on the other said path, a winding on said bridging member, and means for at times supplying to a portion of at least one said path, a flux which does not link said winding but which varies the amount of flux from said source which links the winding.

6. In combination, a source of magnetomotive force, two magnetic paths connected in parallel across said source, a bridging member connecting apoint on one said path with a point on the other said path, a winding on said bridging member, a third magnetic path including a portion of one of said first flnentionned paths between said source and said bridging member, and means for at times sup lying magnetic flux independently to said t ird magnetic circuit to vary the fiux from said source which links said wind- I. In combination, a source of periodically varying magnetomotive force, two magnetic paths connected in parallel across said source, a bridging member connected from a point on one said path to a point on the other said path, a winding on said bridging memher, and means for independently supplying to at least a portion of one said path, magnetic flux which does not thread said winding but which varies the electromotive force induced in said winding by flux from said source.

8. In combination, a magnetic bridge comprising four legs connected in a square, a bridging member connecting two opposite corners of said square, a winding on said bridging member, a source of periodically varying magnetomotive force connected across the other two corners of said bridge,

and means for supplying magnetic flux independently to one leg of said bridge to vary the reluctance of said leg without afiecting the reluctance of the adjacent legs of the bridge.

9. In combination, a magnetic bridge comprising four legs connected in a square and a bridging member connected across two opposite corners of the square, a winding on said bridging member, a source of periodically varying magnetomotive force connected across the remaining two corners of said square, a first magnetic path including one said leg, a second magnetic path including the leg of said bridge opposite said one leg, and

' means for supplying magnetic fluxes to said first and second magnetic paths to vary the electromotive force induced in said windmg.

10. In combination, a magnetic bridge comprising four legs connected in a square and a bridging member connected across two 0pposite corners of the square, a winding on said bridging member, a source of periodically varying magnetomotive force connected across the remaining two corners of said square, a first magnetic path including one said leg, a second magnetic path including the leg of said bridge opposite said one leg, a.

second winding and a third winding located on said first and second magnetic paths respectively, and means for supplying current to said second and third windings to vary the electromotive force induced in said first 50 winding.

In testimony whereof I aflix my signature.

PHILIP H. DOWLING. 

